A25317-A-1119
Owner's Manual for Thern 5FT20 and 5FT25 Captain Series Stationary Davit Cranes
page 5
1.1
Installing the Crane
Do not install the crane in an area defined as hazardous by the National Electric
Code, unless installation in such an area has been thoroughly approved.
Do not install the crane near corrosive chemicals, flammable materials,
explosives, or other elements that may damage the crane or injure the operator.
Adequately protect the crane and the operator from such elements.
Position the crane so the operator can stand clear of the load, and out of the path
of a broken wire rope that could snap back and cause injury.
Attach the crane to a rigid and level foundation that will support the crane and
its load under all load conditions, including shock loading.
1.1.1
CONSULT APPLICABLE CODESAND REGULATIONS for specific
rules on installing the equipment.
1.1.2
LOCATE THE CRANE in an area clear of traffic and obstacles that could
interfere with operation. Make sure the crane is accessible for maintenance
and operation.
1.1.3
INSTALL THE CRANE on a level surface.
1.1.4
FASTEN THE BASE securely to the foundation to withstand applicable
overturning moments and mounting bolt reaction. See Table 1.
a
FOR STANDARD PRODUCTS referred to in this manual, use coarse
thread fasteners, grade 5 or better. Recommended torque for 5/8-inch
coarse threaded grade 5 bolts without lubrication is 150 ft-lb.
Recommended torque for 3/4-inch coarse threaded grade 5 bolts without
lubrication is 260 ft-lb.
Refer to manufacturer's instructions for other fastener types with
specific torque or installation instructions.
b
NON-STANDARD PRODUCTS that vary from the original design may
have different fastening requirements. Contact a structural engineer or
Thern, Inc. for this information.
TO COMPLY WITH LOCAL CODES, CONTACT A QUALIFIED
PROFESSIONAL TO OBTAIN PROPER STRUCTURE OR FOUNDATION
SPECIFICATIONS FOR THE MOUNTING OF THERN PRODUCTS.
Table 1 – Crane Reactions
2
Crane
Model
Mast
Moment
Suggested
Bolt Size
Axial Force
per Bolt
1
5FT20
116,640 in-lbs
13,180 N-m
5/8 inch (M16)
4,700 lbs
20,908 N
5FT25
199,730 in-lbs
22,568 N-m
3/4 inch (M20)
6,430 lbs
28,604 N
1 Force in tension.
2 This information may change without prior notice. It is the responsibility of the installer
and/or end user to ensure the most current information is used.
Important!
• A qualified professional
should inspect or design the
foundation to insure that it
will provide adequate support.
• Locate the crane so it will be
visible during the entire
operation.
